A coalition of civil rights groups called on the Justice Department this week to investigate gun shops in six states that have created "Muslim-free zones."

The Council on American-Islamic Relations, along with the NAACP and 80 other national and state organizations, sent a letter Tuesday to Attorney General Loretta Lynch asking that the shops be investigated. The letter was reported by Mashable.

Six stores in as many states have declared that they will not sell guns to anyone who is Muslim or is perceived to be Muslim at their outlets.

The shops are located in Arkansas, Florida, Kentucky, New York, Oklahoma, and New Hampshire.

"Despite numerous reports of public bans of American Muslims by U.S. businesses, including firing ranges, the DOJ has remained silent in its response to this growing trend of denial of a religious minority’s right of equal access to public accommodations," the letter said.

But Andrew Hallinan, who owns Florida Gun Supply in Inverness, told Mashable that he did not believe the ban discriminated against Muslims.

He instituted the rule in July after the shooting in Chattanooga, Tenn., in which a young Muslim-American man shot four Marines and a Navy sailor.

"I believe the decision to enact that ban is in the interest of public safety, and I believe that there are evil people in this world," he said. "Every other gun shop should take the stand that I took to not arm or train anybody [who is] a threat."